Oxidation at a Dimolybdenum(V) Sulfur Bridge. Formation of SO and SO2 Bridges. Facile Extrusion of SO from the SO2 Bridge

Peroxide oxygenation of μ-thiolate−μ-sulfide Mo(V) dimer complexes of the type [Mo2(NAr)2(S2P(OEt)2)2(μ-O2CMe)(μ-SR)(μ-S)] yielded Mo2(μ-SO) and Mo2(μ-SO2) complexes, demonstrating the reactivity sequence μ-S > μ-SO ≫ μ-SR. Inversion isomers of the pyramidal sulfur site in the μ-SO bridge were observed, and the pyramidicity was confirmed crystallographically. Visible light photolysis of the Mo2(μ-SO2) complex liberated SO from the SO2 bridge and produced Mo2(μ-O) compounds. Crystallography of analogous Mo2(μ-S), Mo2(μ-SO), Mo2(μ-SO2), and Mo2(μ-O) complexes provided structural comparisons related to variations in the bridge functionality. For 2, Mo2C31H44N2O6P2S6: a = 13.604(5) Å, b = 15.280(4) Å, c = 12.502(2) Å, α = 93.36(2)°, β = 112.00 (2)°, γ = 76.01(2)°, triclinic, P1̄, Z = 2. For 3, Mo2C31H44N2O7P2S6: a = 12.535(2) Å, b = 25.299(9) Å, c = 13.989(5) Å, β = 99.99(2)°, monoclinic, P21/n, Z = 4. For 4, Mo2C31H44N2O8P2S6: a = 12.591(9) Å, b = 25.34(1) Å, c = 14.048(3) Å, β = 100.79(4)°, monoclinic, P21/n, Z = 4. For 5, Mo2C31H44N2O7P2S5: a = 13.731(5) Å, b = 19.267(4) Å, c = 16.652(5) Å, β = 104.78(3)°, monoclinic, P21/n, Z = 4.